LAUSR

ABSTRACT In this paper, a novel triple-band microwave chip-less sensor tag is presented for Structural Health Monitoring (SHM) systems. Remote sensing capability of microwave devices is employed here to design a sensor for crack detection in metallic structures. The cracks occurred by natural fatigue or human-made mistakes can be distinguished by desired sensor tags. Triple-band operation of the proposed sensor tag at C and X frequency bands is considered here to precisely detect the narrow-width cracks and their directions. In RCS calculations, the resonant frequencies of the designed sensor tag are displaced at the presence of cracks on its ground plane. The proposed sensor tag can detect cracks with a resolution of 0.2 mm which shows a RCS resonant frequency shift of at least 21.1 MHz. This is a big improvement of detectable range in SHM applications compared to the current sensors.